new power cord or dac?

my system is about 20k. i love it. but my AA ddev3.0 dac is the weakest link. question would i get more bang for the buck by replacing the dac with lets say the perpetual p-3a or upgrading my power cords further? i'm using a shunyata sidewinder on my V.A.C. triode amp. i'm considering getting a BMI WHALE. which would you do? i've found that SOME after-market power cords make a huge improvement but my experience with dac's is lacking. thanks.
I'm a big fan of Stealth power cords (full disclosure: I know the designer, and so have a bias), but I think you'd be much better off replacing the DAC first. Anyone disagree? There are a lot on the used market that would beat the AA, in almost everyone's opinion, and some at good prices.
While my experience is much more power cords than dac's, i agree that i suspected that the dac would be more beneficial, but having no first-hand knowledge i tossed my query out there. i've had insides suggest that my dac is fine but i really questioned what my system would sound like with something more current. much like when i upgraded my old infinite slopes for my Silverline Sonatinas, time marches on. thanks again. mike